Brian O'Driscoll says Grand Slam-chasing England "aren't owed anything" and that Ireland will prey on the nerves he is certain will be present in a team chasing a Six Nations clean sweep on Saturday.

England's players have spoken of a newfound confidence flowing through the reinvigorated squad but O'Driscoll, who led Ireland to the Grand Slam in 2009, knows there will be jitters creeping into his rivals in Dublin.

England are chasing a first clean sweep since 2003 but O'Driscoll has turned up the heat on the opposition, warning them Ireland would be more than happy to ruin their bid for a perfect tournament.

"I don't know too many of the England team and whether there is a new breed coming through full of confidence," said the captain. "I'm sure there will certainly be a number of those within their squad.

"But they will have some nerves like you would for any Grand Slam game and it's our job to try to bring those nerves out and compound them. You understand that and if you see a potential frailty you have to go after that. Just because you find yourself at the big occasion it doesn't mean you are owed anything. You still have to grind it out."

O'Driscoll was captain in 2003 when Ireland and an England team led by Johnson collided in a Grand Slam decider at the old Lansdowne Road. The Irish were blown away 42-6 but O'Driscoll, the only survivor from the starting line-up, credits the result for launching a trophy-laden era.

"When you have won four games your confidence is reasonably high, but the better team won on the day and in going on to win the World Cup they proved the quality of side they were," he said. "We were shown how to play a powerful, dominant game. That was the English at their best. It was part of a learning curve that brought us a Triple Crown the following year and the Grand Slam, albeit six years later.

"Like all games you learn something from it and try not to make the same mistakes again and subsequently we probably did that. If you want to compare the England teams then and now, in 2003 they had been denied a Grand Slam on three previous occasions. They kept knocking on the door until they were finally let in."

Ireland are one loss away from equalling their worst Six Nations performance of 2008 and enter their last competitive match before the World Cup with issues on multiple fronts. Discipline, confidence, selection and tactics have all come under the microscope during a torrid championship, yet there is no inferiority complex against England.

Ireland were the first team to beat the newly-crowned world champions in 2004 and have since prevailed in the fixture six out of the last seven meetings. O'Driscoll is determined for them to extend that sequence by ruining the Grand Slam party.

"I can never remember a victory against England that has been brushed over," said the Leinster centre, who on Saturday will equal John Smit's Test captaincy record of 76 games. "It's always a huge game for us because of the history between the countries and because of the anticipation of the whole nation, not just the rugby supporters, any time we play England.

"The fact England are playing for a Grand Slam heightens the anticipation from an English perspective, but also to a degree from an Irish perspective in that there is an opportunity for us to deny them something. It is also a chance to finish this topsy turvy Six Nations on a high with more wins than losses and with a good taste."

Ireland's prospects of staging an upset could be harmed by the ongoing uncertainty at fly-half. Under Declan Kidney's controversial rotation policy in the position, Jonathan Sexton has been preferred ahead of Ronan O'Gara, who started the last two games.

Sexton endured a difficult afternoon when he entered the fray with 30 minutes remaining in Saturday's 19-13 defeat by Wales, arriving at a point when Ireland were ahead. The chopping and changing can be doing neither player nor team much good, but Kidney has persisted with the experiment.

Luke Fitzgerald has been dropped following an error-strewn transition from wing to full-back, so Keith Earls takes the number 15 jersey with Andrew Trimble filling the vacancy on the left wing.

Scrum-half Eoin Reddan has been included in the XV but his participation is pending an assessment by a neurologist for the concussion sustained against Wales.